The most popular flash memory storage device currently available in the market is a USB flash drive, also named as a pen drive or thumb drive, as shown in FIG. 1. The structure of the storage device includes a housing A, in which a circuit board is disposed with a flash memory module. To enable the transmission of data between the storage device and a computer, one side of the housing A is protrudingly disposed with a connector B, which in general is a USB (universal serial bus) interface connector. Also, the connector B is adapted onto a slip cover C. Because the connector B has a considerable thickness, the storage device cannot be made thin. Thus, further improvement concerning the thickness of the storage device is required.
In fact, the design difficulties will be encountered in making a flash memory storage device thinner can be summarized as follows:
(1) The insufficient strength of the housing: In making the housing thinner, the strength of the thin metal cannot withstand the stress developed and thus the housing cannot protect the flash memory module disposed inside, leading to a possible damage to the flash memory module.(2) The difficulty in joining the housing: The housing consists of an upper and a lower covers usually made of metal to increase its strength. Metal cannot be joined by heat fusion through high-frequency wave in a way similar to join plastics parts, and thus difficulties will be encountered in the assembling and joining. If the metal housing is replaced with an upper and lower plastics covers, the conventional high-frequency wave may be able to be joined the upper and lower cover; however, the problem of insufficient strength described in (1) may occur.(3) The difficult in mounting the connector: Since a thin storage device is thinner than the available USB interface connector, it would be awkward to see a currently available USB interface connector protruding from its housing. Consequently, it is necessary to provide a thin connector to be mounted inside the housing from which the USB interface connector can protrude outwards to connect with a computer. These problems demand the industry to find ways to overcome.